1. No team-mates; last thing you want is 2 or 3 studs out of the lineup and costing you a week.
2. BPA that you could actually start (Ie don't take 5 WR before grabbing a RB)
3.a Never take a QB higher than round 7.
3.b Never draft more than 2 QBs.
4. Don't get cute with waiver pickups. Most are flash in the pan, and rare is the time they'll actually be a better play than the guys you drafted.

These next ones get IDP specific

5. Haloti Ngata is this only DT worth drafting.
6.a Tackles >>> Sacksmasters, ballhawks. It's a lottery with the latter, the former is just cashing a cheque.
6.b The DE/LB who had 15+ sacks last year (Ie JPP, Cam Wake, Clay Matthews, Jared Allen) never repeats the next year. The year after that, back to beasting.
7. "Don't get too cute wither waivers" doesn't apply to defenders in the first four weeks. Feel free to completely turn over your LB corps. After that though, avoid making any changes unless an injury requires it.
8. Nobody ever scouts safeties. Don't be nobody.